Thanks.
Yes, I had then ended up replacing all my write-file-functions add-hooks with before-save-hook: https://github.com/kaushalmodi/.emacs.d/commit/d89d6333f0978d7fda4af412ecaa5089812b7e26
--
Kaushal Modi
> I also have now started using before-save-hook instead of
> write-file-functions where I don't care about the return values of the
> functions added to the hook.
BTW, the use of before-save-hook is not just so you don't have to care
about the return value. It's also because some functions on
write-file-functions may not be run at all (if some earlier function
returns non-nil because it took care of performing the write).
So even adding a "nil" at the of your function doesn't make it right to
add it to write-file-functions.
Stefan